Go to Settings > Accounts > Add Account > Google.Sign in with the new Japanese Google account. Change Play Store Region: Open the Google Play Store, go to the Account section, and switch to your newly created Japanese Google account. The Play Store should now be set to the Japanese region.
The first game released on Google Play was "Sonic the Hedgehog" by SEGA. It was released on October 7, 2008. In March of 2008, Google released the Android operating system and the first app to be released was "Angry Birds." Since then, there have been over 1.5 million apps released on the Play Store.